65hp Lycoming care and feeding

[Grassroots]

Hi Folks,
I'm looking for information on the care and feeding of the 65hp lycoming.
I have one on my PA-15. I know about keeping the cylinder head nuts torqued, but can't find a torque spec or how often they need to be torqued. What about using the steel locknuts that are found on exhaust systems? Any info regarding the cylinder heads and other things would be appreciated.

Thanks,
Bill

 

[Steve Pierce]

Do you have the manuals on the O-145? I don't think you could get a proper torque using a steel lock nut. I haven't heard of the heads losing torque. We used to have a problem with them blowing the gasket out and obtaining new gaskets for a reasonable price.

 

[Grassroots]

Steve,
Yep, I have all the manuals and even the manual for the MA-2 carb. I was surprised that there is no specific torque value listed for the cylinder head nuts. So far everyone I've talked to says to check the torque on a regular basis, like every 10 to 25 hours. What should I expect to happen if a head gasket blows in flight? Do you know of anyone that can rebuild the cylinder heads and valve train if needed?

Thanks,
Bill

 

[Steve Pierce]

I haven't worked on the O-145 in several years but El Reno had parts and I think they could do head work. I actually got the parts and had a local tractor shop that does a lot of machine work help me do the valve guides and seats. The leaking heads just made a stain and lowered compression test results. We always inspected on pre-flight because we were concern about eroding away part of the head. As I remember I only had problems with one head on one of the two J3s I was maintaining with this engine.

 

[JohnW]

I have a "fix" for both problems mentioned (Steve). A really Old Timer told me to quit fartin' around and put TWO head gaskets under each head next time I was in there and they would never blow again. I immediately questioned him as to what effect increasing the "cc's" of the combustion chamber by adding a gasket would be, at which point he snapped on me and told me if I would get my head outa my [well, you get it] and understand that the original Lyc Manual incorrectly lists the Timing BTDC and if I set it to what the "similar" models in that same Manual prescribed, that I would understand that the claim of "65 hp being a courteous "benefit of the doubt" for the Lycoming and that I wouldn't WORRY about .020" of increased Deck Height!" I am pleased to report that I have had the thirty year experience that he was indeed correct. AS far as "availability" of said gaskets... I haven't needed to look for new gaskets the last twenty years, but when I blew my last "single" I had to buy a "set" of four. After using three of the remaining gaskets on other people's O-145-B2 engines and yet to effect the "double-seal" as recommended (yet), I tried to locate another "set" but struck out!!! At that point, I looked to the future and traced the one remaining "new, old stock" gasket for a pattern (still HAVE that Old Girl...somewhere). I traced it onto the [blank] last page of my original Lycoming O-145 Series Manual. I measured and labeled along with the dimensions and a "proof" length of what six inches was the day I traced it (marked off six inches on that page with my 6" scale). Material was tested by a local metallurgist and confirmed in his opinion to be [what is now known as] .020" 2024-T0.

BTW, the six-inch witness "proof" on my manual page has shrunken about 3/16" over the last 25 years in captivity! (Let us have NO COMMENTS from the Q-Tip Peanut Gallery...of which I am a Member... on this issue, if you please!)

Say, Bill...what's the chances you can scan your Marvel-Schebler MA-2 Manual and email me a copy? I been looking for one of those for thirty years and never scored one! Evem if you can only scan it into single .pdf files, I can compile it into a single usable Manual again. I could easily get a copy of that over to MGF Andy who would no doubt be pleased to add it to his site of Handy Dandy material.

 

[Steve Pierce]

That is good to know John. The nice thing about these old airplanes is things were pretty simple back when they were built.